Just to report my success and to encourage other proud new owners I wanted to inform you that flashing the cute little DM-15cc with MEM80 and MEM1b firmware worked just fine on an Asus eeePC running under XP/3.

Overall, my keyboard is ok, I only have problems making the EEX/pi and + keys register. That sometimes takes a few more presses...

By no means the DM-15cc could replace any original HP machine, but due to its credit card size it is an easy to carry allways-in-my-pocket-calculator that has amazing powers. Still, I already thought about selling it again because I have quite large hands...but who on the auction site would know what it was?!? ;-)